I bonked cycling from Lancashire and the lake district to London, England in 1984. I had to stop, dismount, and lie down in a field of grass behind a hedge. I did not like the feeling. I heated water and mixed it with some sort of instant cereal and ate. I was ok within 30 minutes. You have to eat right and keep the energy coming at a steady pace. It can take two hours after eating before the digestive system can deliver energy from that food to your muscles. Energy from freshly extracted juices is assimilated much faster than from bulk food. With a two hour+- hiatus between eating and energy it is a good idea to keep snacking and save meals for the morning and the night. In some places there seem to be endless lines of convenience stores. C-store is often synonymous with junk food, highly refined carbohydrates, empty calories, devitalized foods, and bananas for 89 cents each.
Some have nice delis and tables and chairs. Traveling cross country by bike in the raw, meaning following an arbitrary route as opposed to a mapped route, is a sure path to diarrhea, dysentery or worse if you eat in a lot of restaurants. Sooner or later you will come across some enchilada palace whose food handler was out guzzling beer and smoking cigars during the lessons on personal hygiene and public sanitation, and after that it's Immodium, aspirin, gimme a shot of them there anitbiotics. Van Horn, Texas is one town on the ST where cyclists have met with Geronimo's revenge. I ought to know. I got it every time I stayed a few days and entrusted my health to VH's restaurants. I have read journals of others who had the same problem in the same place.